PNG ICO ICNS MORE
Gaming & gambling
3D
Free Game Icons
warning, Blaze, Attention
Black
64x64
danger, Explosion, Bomb
Photography & graphic design
32x32 Free Design Icons
warning
32x32
Mixed
Iconza
Signs & symbols
Free 3d Glossy Interface Icon Set
Attention, Error, cautious
Hand, warning, Abort
warning, danger, Alert
Prompt, danger, exclamation
Prompt, help, danger
Business & finance
Shimmer Icons
warning, Alert
256x256
Refresh CL
security, warning
PNG MORE
UI
Crystal Office Collection
warning, 24
24x24
Computer & hardware
iMod
warning, siren, robbery
512x512
Vista Style Base Software
Attention, Alert, Achtung
grey, warning, shield
Network & communications
BeOS
beos, warning, Alert
128x128
Discovery
Dialog, warning